Bill Naylor profiles two of the UK’s smallest birds: the firecrest and the goldcrest. They may be diminutive in size, but make up for this with their inquisitive nature and bright plumage
Small warbler-type foreign birds, such as white eyes, have been frequently kept in captivity. But apart from those hand-reared by wildlife hospitals and rehab centres, warblers and related species like the kinglets are virtually unknown to aviculture.
The kinglets (Regulidae) are the family to which the goldcrest (Regulus regulus) and firecrest (R. ignicapilla) belong. It derives from the word “regulus”, which means petty or small king, and refers to the bright-coloured crowns possessed by most of the seven species in the family.
Unlike some other species of kinglet – such as the ruby-crowned (R. calendula), which is considered to be one of the finest North American songsters – the goldcrest and firecrest don’t have outstanding vocals. The former has a very high-pitched rapid seedli-ee, seedli-ee, seedli-ee call ending in a trill. The firecrest’s harsher, monotonous, zit-zit call is lower in tone and has no trill.
It is not surprising that bird catchers ignored both species when the keeping of native birds for their song was fashionable. These two birds’ secretive habits have also meant they were rarely written about at length by naturalists or figured in folklore; although, in past times the names wren and goldcrest were often interchangeable. For many years, the firecrest was considered a variety of the goldcrest and wasn’t scientifically recognised until 1820. Like babblers, due to their specialised diet of minute insects, both species have been largely ignored by aviculture.
Awash with colour
If it wasn’t for the initiatives of aviculturist Frank Meadon, who kept warblers and related birds such as firecrests and goldcrests (achieving a number of first breedings with babblers), there would be virtually no avicultural information on these species. The firecrest is sleeker, more colourful and less dumpy than the goldcrest. Despite being the same length, the firecrest weighs slightly more than the goldcrest, making it the UK’s second smallest bird.
Like most of the six species of kinglets, both male goldcrests and firecrests have a vividly coloured crown, which is more yellowish in the goldcrest. The firecrest’s crown is mainly orange and is only slightly edged with yellow. Its main distinguishing feature is the facial markings that are found in juveniles and both sexes. A black eye-stripe runs from the cere, ending in a downward curve; this highlights the white stripe running parallel above it, both absent in the goldfinch. Females of both species are similar, apart from the female firecrest’s black eye-stripe. Both species seen from the rear can also be mistaken for warblers, especially the Pallas’s warbler (Phylloscopus proregulus).
Although they prefer dense cover in thickets and brambles, with clumps of gorse being a favourite haunt, goldcrests and firecrests do venture into view – especially on warm days – and appear oblivious to humans. As they flit about, the goldcrest often with its wings half extended, busily collecting insects, you are often able to venture up close if one remains still. Although both species sometimes inhabit the same locations, they don’t compete for food, as they have different requirements. Goldcrests forage for aphids etc, like leaf warblers. Firecrests possess broader beaks to deal with larger prey, which is sometimes beaten against a branch to subdue it. They also have rictal bristles to protect their eyes from insect bites.
For a long time, the firecrest was considered to be mainly a winter visitor to southern and eastern England. The much more common goldcrest has a large resident breeding population found over most of the UK, but whose numbers are increased in autumn by migrating birds from Scandinavia. The first recorded firecrest breeding in the UK is often stated as being in 1962, but T.A. Coward records a successful breeding in 1927. Its European population has steadily increased and it now breeds in mainly southern parts of the UK, where there are overwintering populations. The firecrest has a host of old country names including: “fire-crested wren”, “fire crowned kinglet” or “fire-crested kinglet” and the quaint “tidley goldfinch”.
Habitat requirements
The goldcrest (traditionally known as the gold-crested wren) is mainly attracted to conifers, while the firecrest will frequent deciduous trees – it has a particular liking for Norway spruce. Yews, especially old specimens often found in churchyards, attract both these species. Frank Meadon recommended that conifers and a bushy yew should be located in the aviary, which the birds will spend a lot of time investigating.
As with all small birds, food is an obsession and they require regular amounts to fuel their metabolism. Apart from some evidence of them visiting bird tables for fatty foods and observations of them feeding on pollen, they feed exclusively on invertebrates, their larvae and eggs. Unlike firecrests, goldcrests will join groups of other birds, such as tits, as they move from one feeding area to another. Whether this is connected with food or because they feel vulnerable on their own is not known.
An aviary for firecrests or goldcrests requires plenty of foliage and ground-cover plants to encourage invertebrates, plus a frost-free shelter. Even with additional livefood such as mealworms, wax moths and fruit flies, this should not be relied upon to supply all the nutrients, and protein-rich softfood should form part of the diet. Individuals vary in their readiness to eat softfood and rehabilitated birds have to be force fed before they will accept it. Sometimes housing a pair of Bengalese finches, who will sample any food, in the same aviary will encourage them to sample inanimate food. Frank Meadon found grated cheese was a valuable food for firecrests and goldcrests. As with all migratory birds, they require a high fat intake.
Breeding behaviour
Nesting habits are similar in both species. But courtship rituals are sufficiently different to provide a barrier against hybridisation. Even when captive individuals of each species, which are always eager to breed, have been kept together, hybridisation has never occurred. The different firecrest species are considered closely related and hybridisation in captivity readily occurs. But successful breeding of the Eurasian firecrest as yet is unrecorded.
Although the respective courtship displays are different, both species rely greatly on displaying the coloured crown. Wings extended, perched in an open area so that sunlight illuminates the bird’s crown, the firecrest raises its crest, spreading it sideways so that the flame patch is displayed.
The nests of both species are located quite high 4.5-6m (15-20ft) from the ground. Goldcrests nest mainly in coniferous trees, while firecrests usually choose deciduous trees. Female goldcrests and firecrests construct the nest from grass and moss, lined with small feathers, wool or hair. The deep nest is slung like a hammock between two thin branches and is sometimes interwoven into ivy of an adjacent tree.
Seven to 10, sometimes as many as 13, brownish, reddish spotted eggs are laid in April or early May and are incubated by the female for up to 16 days.
Nestlings are initially given aphids, which are fed with a combination of tiny fragments of snail shells. Larger insects are phased in later. Fledging occurs around 10 days. By this time another clutch has been laid and, when these hatch, the parents have their work cut out feeding almost 20 youngsters. But hard winters take a big toll on goldcrest and firecrest numbers, and large clutches are a safeguard against a drop in population.
Bill Naylor has enjoyed a 40-year career in ornithology and aviculture.
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